@article{178084,
      note = {"A summary of ⁴⁰Ar/³⁹Ar age analyses of eighteen  samples of volcanic rocks from the Challis Volcanic Group  and a summary of basin stratigraphy in southwestern  Montana."},
      author = {M'Gonigle, John W. and Dalrymple, G. Brent.},
      url = {http://library.usi.edu/record/178084},
      title = {⁴⁰Ar/³⁹Ar  ages of some Challis Volcanic Group  rocks and the initiation of Tertiary sedimentary basins in  southwestern Montana /},
      publisher = {U.S. G.P.O. ;},
      recid = {178084},
      pages = {iii, 17 p. :},
      address = {Washington :},
      year = {1996},
}